Similarity in orientation effects on thermal conductivity and flow birefringence for polymers—polydimethylsiloxane

Experimental results on flow birefringence and thermal conductivity measured under shearing strain conditions for liquid polydimethylsiloxane are presented. Both phenomena show similar dependency on strain rate, and this dependency is attributed to net orientation of the macromolecules. An orientation model is presented and is shown to be qualitatively correct.